In fact, I will suggest different way to handle the originally problem.
The example listed originally comes with a Java Function doesn't use any
instance fields/methods, so serializing the whole class is a overkill solution.
Instead, you can/should make the Function static, which will work in the logic
of that function tries to do, and it is a better solution than marking the
whole class serializable.
The whole issue is that the function is not static, but doesn't use any
instance fields or other methods. But Spark sends the non-static function call,
it has to wrapper the whole class which contains the function as a whole
closure through network, and in this case, it requires the whole class to be
serializable.
Yong
________________________________
From: 颜发才(Yan Facai) <facai....@gmail.com>
Sent: Saturday, March 11, 2017 6:48 AM
To: 萝卜丝炒饭
Cc: Mina Aslani; Ankur Srivastava; user@spark.apache.org
Subject: Re: org.apache.spark.SparkException: Task not serializable
For scala,
make your class Serializable, like this
```
class YourClass extends Serializable {
}
```
On Sat, Mar 11, 2017 at 3:51 PM, 萝卜丝炒饭
<1427357...@qq.com<mailto:1427357...@qq.com>> wrote:
hi mina,
can you paste your new code here pleasel
i meet this issue too but do not get Ankur's idea.
thanks
Robin
---Original---
From: "Mina Aslani"<aslanim...@gmail.com<mailto:aslanim...@gmail.com>>
Date: 2017/3/7 05:32:10
To: "Ankur
Srivastava"<ankur.srivast...@gmail.com<mailto:ankur.srivast...@gmail.com>>;
Cc:
"user@spark.apache.org<mailto:user@spark.apache.org>"<user@spark.apache.org<mailto:user@spark.apache.org>>;
Subject: Re: org.apache.spark.SparkException: Task not serializable
Thank you Ankur for the quick response, really appreciate it! Making the class
serializable resolved the exception!
Best regards,
Mina
On Mon, Mar 6, 2017 at 4:20 PM, Ankur Srivastava
<ankur.srivast...@gmail.com<mailto:ankur.srivast...@gmail.com>> wrote:
The fix for this make your class Serializable. The reason being the closures
you have defined in the class need to be serialized and copied over to all
executor nodes.
Hope this helps.
Thanks
Ankur
On Mon, Mar 6, 2017 at 1:06 PM, Mina Aslani
<aslanim...@gmail.com<mailto:aslanim...@gmail.com>> wrote:
Hi,
I am trying to start with spark and get number of lines of a text file in my
mac, however I get
org.apache.spark.SparkException: Task not serializable error on
JavaRDD<String> logData = javaCtx.textFile(file);
Please see below for the sample of code and the stackTrace.
Any idea why this error is thrown?
Best regards,
Mina
System.out.println("Creating Spark Configuration");
SparkConf javaConf = new SparkConf();
javaConf.setAppName("My First Spark Java Application");
javaConf.setMaster("PATH to my spark");
System.out.println("Creating Spark Context");
JavaSparkContext javaCtx = new JavaSparkContext(javaConf);
System.out.println("Loading the Dataset and will further process it");
String file = "file:///file.txt";
JavaRDD<String> logData = javaCtx.textFile(file);
long numLines = logData.filter(new Function<String, Boolean>() {
public Boolean call(String s) {
return true;
}
}).count();
System.out.println("Number of Lines in the Dataset "+numLines);
javaCtx.close();
Exception in thread "main" org.apache.spark.SparkException: Task not
serializable
at
org.apache.spark.util.ClosureCleaner$.ensureSerializable(ClosureCleaner.scala:298)
at
org.apache.spark.util.ClosureCleaner$.org$apache$spark$util$ClosureCleaner$$clean(ClosureCleaner.scala:288)
at org.apache.spark.util.ClosureCleaner$.clean(ClosureCleaner.scala:108)
at org.apache.spark.SparkContext.clean(SparkContext.scala:2094)
at org.apache.spark.rdd.RDD$$anonfun$filter$1.apply(RDD.scala:387)
at org.apache.spark.rdd.RDD$$anonfun$filter$1.apply(RDD.scala:386)
at
org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:151)
at
org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:112)
at org.apache.spark.rdd.RDD.withScope(RDD.scala:362)
at org.apache.spark.rdd.RDD.filter(RDD.scala:386)
at org.apache.spark.api.java.JavaRDD.filter(JavaRDD.scala:78)
